Electrical double layer at dielectric liquid/solid interface. Space charge measurements using the thermal step methods

The experimental evidence of the electrical double layer (EDL) at the dielectric liquid-solid interface is an important question. It is a fundamental problem which has given several physical models and numerous industrial applications concerning electrical engineering (transformers, wet cables and capacitors). The thermal step technique, recently, has shown its great sensitivity in measuring space charge in several geometries, particularly in cables. This method has been tried here in order to verify the assumptions made in models established several years ago.